Offshore platform structure has the ability to resist wave loading, wind loading, operation loading, and ship collision, therefore, it is important to investigate the structural behavior of platform taking into consideration soil-structure-pile interaction when the platform is subjected to ship impact at a different location on deck slab. The present study deals with platform supported by pile foundation. The effect of soil-pile interaction on behavior of platform to lateral impact load is investigated by using finite element simulation which is performed by ABAQUS software. From the results obtained, it is obvious that the ship collision position on platform will be reflected on ultimate capacity of structure so the structure will undergo to loose ultimate capacity due to damage that occurs from the ship collision. This study comprises investigation of pile lateral displacement, pile twist angle, pile shear force distribution, pile bending moment distribution and deck slab displacement. It also clarifies that the pile displacement has been reflected on pile critical length. The twist angle of the pile is more sensitive to soil type and loading condition. It is seems that the shear force distribution and bending moment distribution are affected by loading condition and soil type. Finally this study shows that the response of deck slab depends on soil type, soil-pile interaction and loading condition.

Many structures are subjected to torsional and horizontal loads in addition to vertical load lead that the foundation of these structures may be collapsed. The proposed model for pile groups consists of an elastic beam-column that represents the pile, rigid cap and nonlinear spring to simulate the soil. In the horizontal direction, the p-y curve method is used to calculate the subgrade reaction of soil while the τ-0 curve method and the load transfer method are used in the vertical direction. The effect of pile group and load coupling is considered by the p multiplier method in the pile head. A parametric study is carried out under the combined action for horizontal and torsional loads. The study shows that unequal shear force distribution in the head of piles is very significant. The axial force variation in each pile with different length is obtained. The study is very important to take into account the design pile group under combined loads.

In many low-income countries, access to improved sanitation is frequently lacking and nearly 90 percent of sewage is discharged without treatment into water bodies. Even with the immense social and technical developments, many researchers around the world still concentrate on pollution issues. Filter unit which consist of single media or mixed media can be improve by using different material with various physical and chemical properties, so, this property must have positive influence when mixed with original material of filter or in the other word the new material must promote, also alter the hydraulic and environment behavior of filter unit and this will reflect on treatment coast of wastewater and drinking water regardless the source. The inequality in physical and chemical properties of mixed or added material must increase the operation efficiency by reduce the virus and pathogenic, also increase the removal of suspended solid, diminish the water salinity and reduce the concentration of harmful materials. Over all the modified filter unit must work with satisfactory level as compared with standard filter unit considering the operation and maintenance coast. In general, the modification in filter unit lead to the dramatic increase in removal of total suspended solid with increase in COD and BOD 5 level, also increase the removal of chemical material.

The single pile is a structural element that has an important role in supporting any part of the superstructure. This paper adopted three dimensional finite element modelling by using ANSYS to discover the influence of soil size domain on pile diameter, pile length, load eccentricity and torsion magnitude. One type of soil was used and described by Drucker-Prager model. The numerical analysis has been performed to show how the variation in soil size domain effects on the behaviour of single pile under torsion load. The procedure which is adopted in the investigation depends on fixing all variables and changing one variable to show the impact of this variable on the pile response considering soil domain variation. From the investigation, it is obvious that the pile diameter, eccentricity and torsion load have a major influence on the pile response, while the pile length has a minor influence on the pile response. Here, the increase in pile diameter reduces the load transfer to the soil; also the increase in eccentricity increases the load transfer to the soil while the increase in soil domain reduces the pile response. When the torsion load increases the pile response increases too. The pile response refers to displacement, rotation, shear force and bending moment.

This work examines the interaction between two neighbouring structures, a fuel storage tank and a nearby pile group when the pile group is placed under static loads with different loading conditions related to the tank status (empty, half full, and full). Due to the role of soil in transferring load between embedded neighbouring structures, this study deals with soil-structure interaction by assuming that the soil displays nonlinear behaviour. The major factors which play a significant role in the response of the fuel storage tank were thus considered; these factors were defined as the maximum bending moment along the tank wall, the maximum shear force along the tank wall, the hoop stress in all rings of the tank, the maximum pressure distribution along the tank wall, and the maximum lateral displacement along the tank wall. The influence of the distance between these structures on bending moment, shear force, and hoop stresses in the fuel storage tank were also studied. The results suggest that the case of a full liquid storage tank represents a critical state that must be considered when assessing the structural behaviour of the storage tank.